Primum non noccere. Although this old maxim is wrongly attributed to Hippocrates and sometimes to Galen, according to one of the pioneers of American medical ethics, the author of the aphorism was in fact Auguste François Chomel (1788-1858), who succeeded Laennec in the Chair of medical pathology and was the preceptor of Pierre Alexander Louys, a firm critic of bleeding as an iatrogenic intervention. It is nevertheless the antecedent of the principle of non maleficence, or do-no-harm, which is one of the four rules of bioethics. Yet, the real Hippocratic origin lies in the sentence which, in the first book of epidemics, warns physicians that they must always pursue their patients'; well-being or at least avoid harming them. This recommendation is more practical than that of the title since, given the fact that there is no such thing as a medical or healthcare intervention that we can state in absolute terms to be harmless, if we followed it to the letter we would be committing therapeutic nihilism. This amounts to the generation of iatrogenesis by neglect, a way of harming patients who do not take advantage of the benefits to be gained from suitable care.

Another way of harming them, however, is active, as a consequence of medical actions, whether these be of a diagnostic, prophylactic, therapeutic or rehabilitative nature. And in contrast to a very widely held opinion, the side effects of medical and healthcare practices are not only the result of errors or neglect by professionals. Neither can the organisational and structural shortcomings of health systems account for the glaring number of iatrogenic illnesses that occur today, many of which are related to healthcare consumerism and inadequate medicalisation. This has led to the cultivation of a certain medical omnipotence and a pronounced trivialisation of our activities, probably as a consequence of having encouraged exaggerated expectations and superfluous or even futile usages.

Although we do not have accurate figures concerning the current impact of iatrogenesis, we know that it is a significant health problem that, to top things off, is on the rise rather than decreasing. It is therefore a good idea to take a fresh look at ourselves and accept some of the limitations that, as human beings, we will probably never be able to fully overcome. Hence the importance of iatrogenesis - and above all its prevention and control - being included within the syllabi for the training and learning of health science professionals, at both undergraduate and postgraduate levels, and of course during continuing education and periodical recertification. It must go beyond the attention deserved by certain, still scarce, initiatives dealing with patients'; safety, many of which are included within care quality and clinical management programmes. What is needed is an approach based on the ethics of uncertainty and on the ethics of ignorance, capable of fostering the values of the medical profession and, among all of them, that of caution, with the firm purpose of benefiting the patients or, at least, of causing them the least possible harm.

Hence the interest in the report that a work group at the Sociedad Española de Salud Pública y Administración Sanitaria (SESPAS - Spanish Public Health Society) and the Organización Médica Colegial (OMC - Spanish Organisation of Medical Associations) has drawn up, and which the Journal FEM has considered an interesting contribution to publish in this issue.